Prophylactic neural stimulation

Abstract

A method is provided including identifying a subject as being at risk of cognitive decline due to cardiac surgery. The method further includes implanting at least one neural stimulator in a vicinity of a sphenopalatine ganglion (SPG) of the subject, and applying stimulation to the SPG by activating the neural stimulator at least during the cardiac surgery. Other applications are also described.

1 . A method comprising:
 identifying a subject as being at risk of cognitive decline due to cardiac surgery;   implanting at least one neural stimulator in a vicinity of a sphenopalatine ganglion (SPG) of the subject; and   applying stimulation to the SPG by activating the neural stimulator at least during the cardiac surgery.   
     
     
         2 . The method according to  claim 1 , wherein identifying the subject, comprises identifying the subject as not displaying symptoms of cognitive decline. 
     
     
         3 . The method according to  claim 1 , wherein implanting the at least one neural stimulator comprises implanting two neural stimulators, one at each SPG of the subject. 
     
     
         4 . The method according to  claim 1 , wherein applying stimulation to the SPG comprises applying the stimulation for at least one day following the cardiac surgery. 
     
     
         5 . The method according to  claim 4 , wherein applying stimulation to the SPG comprises applying the stimulation for up to five days following the cardiac surgery. 
     
     
         6 . The method according to  claim 1 , wherein applying stimulation to the SPG comprises applying the stimulation only during the cardiac surgery. 
     
     
         7 . The method according to  claim 1 , further comprising:
 monitoring the subject to identify an adverse effect of the stimulation to the SPG; and   discontinuing application of the stimulation to the SPG, if an adverse effect of the stimulation is identified.   
     
     
         8 . The method according to  claim 1 , wherein implanting the at least one neural stimulator comprises advancing the at least one neural stimulator through a greater palatine canal of the subject to the SPG of the subject. 
     
     
         9 . A method comprising:
 identifying a subject as being at risk of cognitive decline due to cardiac surgery;   implanting at least one neural stimulator in a vicinity of a sphenopalatine ganglion (SPG) of the subject;   during the cardiac surgery, using Doppler sonography to detect a presence of an embolism; and   applying stimulation to the SPG by activating the neural stimulator if the embolism is detected, and withholding the application of stimulation to the SPG if an embolism is not detected.   
     
     
         10 . The method according to  claim 9 , wherein identifying the subject, comprises identifying the subject as not displaying symptoms of cognitive decline. 
     
     
         11 . The method according to  claim 9 , wherein using Doppler sonography comprises using carotid Doppler ultrasound. 
     
     
         12 . The method according to  claim 9 , wherein using Doppler sonography comprises using transcranial Doppler sonography. 
     
     
         13 . The method according to  claim 9 , wherein using Doppler sonography comprises detecting whether the embolism includes a blood clot, and wherein applying stimulation comprises applying stimulation if the blood clot is detected. 
     
     
         14 . The method according to  claim 13 , further comprising adjusting a parameter of the applying of the stimulation to the SPG in response to detecting the blood clot. 
     
     
         15 . The method according to  claim 9 , wherein using Doppler sonography comprises detecting whether the embolism includes an air embolism, and wherein applying stimulation comprises applying stimulation if the air embolism is detected. 
     
     
         16 . The method according to  claim 15 , further comprising adjusting a parameter of the applying of the stimulation to the SPG in response to detecting the air embolism. 
     
     
         17 . The method according to  claim 9 , wherein using Doppler sonography to detect a presence of an embolism comprises using Doppler sonography to differentially indicate the presence of a blood clot or an air embolism. 
     
     
         18 . Apparatus comprising:
 a Doppler sonography device configured to detect a presence of an embolism;   an implantable neural stimulator configured for implantation in a vicinity of a sphenopalatine ganglion (SPG) of the subject; and   control circuitry configured to drive the implantable neural stimulator to apply electrical stimulation to the sphenopalatine ganglion (SPG), if the embolism is detected by the Doppler sonography device.   
     
     
         19 . The apparatus according to  claim 18 , wherein the embolism includes a blood clot and wherein the apparatus is configured to detect the presence of the blood clot. 
     
     
         20 . The apparatus according to  claim 18 , wherein the embolism includes an air embolism and wherein the apparatus is configured to detect the presence of the air embolism. 
     
     
         21 . The apparatus according to  claim 18 , wherein the embolism includes an embolism selected from the group consisting of: a blood clot and an air embolism, and wherein the apparatus is configured to differentially indicate the presence of a blood clot or an air embolism. 
     
     
         22 . The apparatus according to  claim 18 , wherein the Doppler sonography device comprises a carotid Doppler ultrasound. 
     
     
         23 . The apparatus according to  claim 18 , wherein the Doppler sonography device comprises a transcranial Doppler sonography. 
     
     
         24 . The apparatus according to  claim 18 , wherein the control circuitry is configured to withhold the application of stimulation to the SPG if an embolism is not detected.